Boron-Based Flame Retardants: Enabling Everyday Safety

Summary

On November 6, 1961, one of the most costly and destructive residential fires in California history ignited. Especially dry conditions and strong Santa Ana winds (blowing up to 50 miles per hour) accelerated the fire’s spread. Called the “Bel Air Fire,” this nightmare ripped through one of the most high-profile neighborhoods in the country, home to several famous actors and even then Vice President Richard Nixon. In total, the fire destroyed 484 homes and burned more than 6,000 acres. U.S. Borax played an instrumental role in stopping the fire by supplying powdered borate ore to firefighting crews for a flame-retardant mixture. The crews added water to the borate, then loaded it onto repurposed B-17 bombers. Nicknamed “Borate Bombers,” pilots flew these planes over the fire and dropped the compound to curb its spread. Firefighters eventually controlled the flames and extinguished the fire two days later. Photo by Grey Villet Afterwards, the city of Los Angeles enacted several laws and fire safety policies, including banning wood shingle roofs. While these measures were overdue, they fell short of addressing the underlying problem: Highly combustible materials surrounding people needed an effective flame retardant. This need drove our researchers into action. We started testing formulations, looking for a compound that could prevent and mitigate fire damage. After a decade of research and development, we released our first zinc borate fire retardant, Firebrake®, into the market. Boron’s use as a flame retardant One of the earliest uses of boron as a flame retardant was in the 18th century when Obadiah Wyld patented a mixture for flame retardant clothing. During the mid-20th century, firefighters used borate powder mixed with water to combat wildfires before eventually replacing it with an ammonium phosphate compound. After the Bel Air Fire revealed the inherent flammability risk of common materials, we started researching how to create a new boron flame retardant to ...